2023 Chicago Men's Challenger – Singles

Roman Safiullin was the defending champion but chose not to defend his title.

Alex Michelsen won the title after defeating Yuta Shimizu 7–5, 6–2 in the final.

Seeds
• # 🇦🇺 James Duckworth (withdrew)

• # 🇺🇸 Aleksandar Kovacevic (second round)

• # 🇪🇨 Emilio Gómez (first round)

• # 🇨🇳 Shang Juncheng (semifinals)

• # 🇹🇷 Altuğ Çelikbilek (first round)

• # 🇨🇦 Alexis Galarneau (first round)

• # 🇫🇷 Giovanni Mpetshi Perricard (semifinals)

• # 🇺🇸 Steve Johnson (first round)